Variously configured devices of the pre-cited type are known in the technical field and depending on their principle of operation, they can be divided into so-called axial piston adjusting devices and so-called vane-type adjusting devices. In the case of axial piston adjusting devices, the hydraulically actuated adjusting element is constituted by an axially displaceable adjusting piston which cooperates with helical gears on the element attached to the crankshaft and on the element attached to the camshaft, while in vane-type adjusting devices, the hydraulically actuated element is constituted by a number of radial vanes on the element attached to the camshaft which are displaceable within pressure chambers in the element attached to the crankshaft.
For a supply of these devices with the required hydraulic pressure medium, the elements of such devices attached to the camshaft, independently of their principle of operation, are connected, similar to the disclosure of DE-OS 195-02 496, generally on their camshaft-proximate side to a pressure medium adapter surrounding the camshaft and comprising on its peripheral surface, annular pressure medium channels as well as pressure medium ducts starting from these annular channels and leading to the device. This pressure medium adapter is surrounded by a connecting bracket which is fixed in the cylinder head of the internal combustion engine and receives the solenoid control valve for the actuation of the adjusting piston. A pulse emitter wheel which is equally essential to the functioning of these devices and which, together with the pulse reading device serves to constantly control the position of the camshaft relative to the crankshaft, is secured in these devices in most cases to the end of the camshaft opposite the device or it is screwed together with the device on the camshaft-remote end thereof onto the camshaft.
A drawback of such solutions, however, is that the components required for the pressure medium supply and the pulse emitter wheel including the pulse reading device are arranged separately from each other on the camshaft or in the cylinder head of the internal combustion engine and thus involve a large number of individual parts which increase the costs for the modification and manufacture of an internal combustion engine intended to be equipped with a camshaft adjusting system. A further drawback has proved to be their difficult and complicated accessibility for repair and maintenance work.
Further, according to the disclosure of DE-OS 42 18 078, it is also known to supply the necessary hydraulic medium to a device for varying the timing of gas exchange valves of an internal combustion engine from its camshaft-remote end. The device is therefore arranged in continuation of the camshaft to protrude sidewards cut of the cylinder head and is surrounded by a cap. On the inner surface of the cap there is fixed concentric to the camshaft, a non-rotatable oil distributing element which is surrounded by a bushing of the element of the device attached to the camshaft and comprises separate pressure medium ducts leading to the pressure chambers of the device.
This solution likewise has the drawback that due to structural conditions, a pulse emitter wheel with the associated pulse reading device essential to the functioning of the device can be arranged on the camshaft or in the cylinder head only separately from the elements required for assuring pressure medium supply, i.e. either near the camshaft-proximate end of the device or on the end of the camshaft opposite from the device. Thus, in these solutions too, a number of individual parts are required which disadvantageously increase the costs of modifying and manufacturing an internal combustion engine intended to be equipped with a camshaft adjusting system and which, similar to the previously discussed solutions, are difficult of access for repair and maintenance.